Apparatus for automatic refuelling of vehicles

ABSTRACT

Apparatus for the automatic refuelling of vehicles, primarily cars, including a robot which includes a robot head that is movable in relation to the robot so as to bring the robot head to a predetermined position in relation to the vehicle fuel tank pipe. The positioning of the robot head is effected by a positioning system which includes a first part located on the robot head and a second part placed in a predetermined position on the vehicle, wherein the robot head includes an outer tube and an inner tube which can be moved within said outer tube and extended out of said tube. The outer tube is resilient or yieldable, and the free, front end of the outer tube has the shape of a truncated cone that docks with a correspondingly conical part of an adapter attached to the upper orifice of the vehicle fuel tank pipe during said positioning operation. After the docking operation, the free forward end of the inner tube projects outwardly to a position down into the fuel-tank pipe, whereafter fuel is delivered to the fuel tank through the inner tube.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to apparatus for the automatic refuellingof vehicles.

2. Description of the Related Art

Swedish Patent Specification No. 8901674-5 describes an apparatus forthe automatic refuelling of vehicles, primarily cars, which includes arobot having a robot head provided with a fuelling nozzle or likedevice, and which is constructed to move the fuelling nozzleautomatically from a rest position to a vehicle fuelling position inresponse to sensing and control means, and after the vehicle has beenplaced in a predetermined position relative to the robot.

According to that patent specification, the refuelling nozzle includes arigid, first tubular element, preferably a metal tube, which is intendedto be connected by the robot to an adapter which is provided with a holeand which is attached to the upper orifice of the vehicle fuel-tankpipe. A flexible, second tube, preferably of a plastic tube material, isarranged within the first, rigid tube for movement between a first endposition in which the outer, free end of the second tube is locatedwithin the first tube, to a second end position in which the second tubeprojects out from the first tube. A tube connection is provided betweensaid hole and the vehicle fuel-tank pipe. The robot is constructed tomove the free end of the first tube into abutment with, or to a positionin the immediate vicinity of the adapter in a first movement step and tomove the free end of the second tube out of the first tube and down intosaid tube connection or down into the fuel-tank pipe of the vehicle in asecond movement step, and to pump fuel through the second tube and downinto the fuel tank of the vehicle in a third step. When fuelling of thevehicle is completed, the robot repeats the two first-mentioned steps,but in the reverse order.

A positioning system as mentioned in the aforesaid patent applicationincludes a transceiver unit mounted on the robot head, which transceiverunit operates at microwave frequency, and a passive transponder isplaced on the vehicle in a predetermined position relative to thefuel-tank pipe.

Although the robot head is positioned very accurately in relation to thevehicle fuel-tank flap, or cover plate, and therewith in relation to thefuel-tank pipe, the load acting on the vehicle can change from the timeat which the robot head is initially positioned to the time at whichfuelling of the vehicle is commenced. This change in load may be causedby a person leaving the vehicle, for instance.

Furthermore, when positioning the robot head it is necessary to be ableto accept within accepted tolerances deviations caused by measuringerrors or by an incorrectly positioned transponder on the vehicle.

It is thus desirable to be able to permit certain deviations between theideal position of the robot head and the fuel-tank pipe when dockingbetween the first, outer tube and the fuel-tank pipe, and the actualposition occupied by the robot head immediately prior to docking.

Another problem is that docking must be monitored both prior to andduring a fuelling operation, so that fuelling can be carried out in asafe manner.

These desiderata are fulfilled by the present invention.

SUMMARY OF THE INVENTION

The present invention thus relates to apparatus for the automaticrefuelling of vehicles, preferably cars, including a robot having arobot head that is movable in relation to the robot so as to bring therobot head to a predetermined position in relation to the vehicle fueltank pipe. The positioning of the robot head is effected by apositioning system which includes a first part located on the robot headand a second part placed in a predetermined position on the vehicle,wherein the robot head includes an outer tube and an inner tube whichcan be moved within said outer tube and out of said outer tube. Thefree, front end of the outer tube has a part in the shape of a truncatedcone, said part being intended to be docked with a correspondinglyconical part of an adapter, a truncated-conical part, during saidpositioning operation, said adapter being attached to the upper orificeof the fuel-tank pipe. Subsequent to said docking operation, the freeforward end of the inner tube is intended to project out to a positiondown in the fuel-tank pipe, whereafter fuel is delivered to the fueltank through the inner tube. The forward end of the inner tube has anessentially conical shape, and in said positioning operation, the innertube has an axially displaced position relative to the outer tube suchthat the forward end of said inner tube will coact with the outersurface of the truncated cone of the outer tube to form a generallyconical front part. The outer tube is resilient or yieldable so thatsaid docking procedure is able to take place, provided that the tip ofthe inner tube is positioned radially inwards of the base of the conicalpart of the adapter.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in more detail partially withreference to exemplifying embodiments thereof shown in the accompanyingdrawings in which:

FIG. 1 is a side view of the front part of the robot head prior to finaldocking of the head with an adapter attached to a fuel-tank pipe;

FIG. 2 is a cut-away view of the front part of the robot head;

FIG. 3 illustrates a part of the forward part of the robot head and apart of the adapter;

FIG. 4 illustrates ongoing docking between the forward part of the robothead and the adapter, and shows a deviation between the actual and theideal position;

FIG. 5 illustrates the position of the robot head upon termination ofthe docking procedure shown in FIG. 4;

FIG. 6 illustrates conditions immediately prior to commencing arefuelling operation;

FIG. 7 illustrates the front part of the robot head, as seen from theright in FIG. 1; and

FIG. 8 illustrates an alternative configuration of the forward end of aninner tube.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 is a side view of the forward part of a robot head 1 andillustrates said part in a position prior to final docking of the robothead with an adapter 3 attached to the fuel-tank pipe 2 of the vehicle.The robot head belongs to a robot which is not shown in the Figure. Therobot head 1 is movable in relation to the robot, so that the robot headcan be brought to a predetermined position in relation to the fuel-tankpipe 2 of the vehicle, or more specifically in relation to the adapter3.

The positioning is made by means of a positioning system which includesa first part located on the robot head and a second part which is placedin a predetermined position on the vehicle. The positioning system ispreferably of the kind defined in the introduction, wherein the secondpart of the system is a passive transponder which is mounted on thevehicle in the vicinity of or actually on the vehicle fuel-tank flap.The positioning system, however, is not significant to the presentinvention.

The robot head includes a fuelling nozzle which, in turn, includes anouter tube 4 and an inner tube 5 which is able to move within the outertube and out of said tube, see FIG. 2. The free, forward end of theouter tube 4 includes a part 6 in the form of a truncated cone, thispart being intended to be docked with a corresponding conical part 7 inthe form of a truncated cone on the adapter 3 attached to the upperorifice of the fuel-tank pipe during said positioning procedure. Thefree forward end 8 of the inner tube 5 is intended to be extended to aposition further down in the fuel-tank pipe, see FIG. 6, upon completionof the docking procedure, whereafter fuel is delivered through the innertube.

According to the invention, the aforesaid forward end 8 of the innertube 5 has a generally conical configuration. When positioning the robothead relative to the fuel-tank pipe, the axially displaced position ofthe inner tube 5 relative to the outer tube 4 is such that the forwardpart 8 of the inner tube will coact with the outer surface of thetruncated cone 6 of the outer tube so as to form a generally conicalforward part of the robot head.

As will be seen from FIG. 2, among other things the forward end 8 of theinner tube 5 is smoothly rounded so as to provide a blunt point. Thisrounded forward end, however, coacts with the conical part 6 of theouter tube and a generally conical front part of the robot head. FIG. 8illustrates an alternative configuration of the forward end 8 of theinner tube, namely a configuration in which the forward end 8 is muchmore pointed and in which a more accurate fit in the frusto-conical part7 is achieved.

As shown only in FIGS. 7 and 8, the inner tube 5 of both of theseembodiments is provided with openings 9 in its forward end 8, whichallow fuel to pass through the inner tube and into the fuel-tank of thevehicle.

According to the invention, the outer tube 4 is sufficiently resilientor yielding to enable docking to take place provided that the forwardend 8 of the inner tube 5 is positioned radially within the base 10 ofthe conical part 7 of the adapter 3. When docking is completed, see FIG.5, the conical surfaces 6, 7 of the robot head and the adapter,respectively, abut one another.

It is mentioned above that the outer tube 4 is sufficiently resilient oryielding to enable docking to take place provided that the forward end 8of the inner tube 5 is positioned within the base 10 of the conical part7 of the adapter 3, see FIG. 1. Provided that the inner tube 5 meets theconical part 7 of the adapter 3 as the inner tube 5 is projected outfrom the outer tube 4, the inner tube 5 will be guided down into theadapter 3 and therewith into the fuel-tank pipe 2. In the case when theforward end 8 of the inner tube does not come ideally into directcontact with the adapter opening 11 as the inner tube 5 is extended fromthe outer tube 4, it is necessary for the outer tube 4 to be deformed inorder to enable the inner tube 5 to be guided down into the adapter 3.

Thus, the largest positional error of the robot head 1 relative to thefuel-tank pipe 2 that can be permitted is one in which the forward end 8of the inner tube 5 is located within the base 10 of the conical part 7of the adapter as the inner tube 5 is forwardly extended. According tothe invention, the outer tube 4 shall be yieldable to an extent such asto allow effective docking to be achieved in the maximum permitted wrongpositioning of the inner tube 5.

The base 10 of the conical part 7 of the adapter may have a relativelylarge diameter, for instance a diameter of from 5 to 10 centimeters.

Thus, the permitted positional error of the robot head 1 relative to thefuel-tank pipe 2, or to the adapter 3, is much greater than the largestpositional error that occurs as a result of measuring errors obtained inthe positioning system. The difference in the height position of a carcaused by a person leaving the vehicle is only one or more centimeters.The positioning problem mentioned in the introduction is therewithsolved by means of the present invention.

FIGS. 4 to 6 illustrate a docking operation. In FIG. 4 the broken line12 illustrates the inner tube 5 subsequent to having been extended fromthe outer tube 4, wherewith the forward end 8 of the inner tube 5 liesagainst the conical part 7 of the adapter 3. When the inner tube 5 isfurther extended from the outer tube 4 (see FIG. 5), the conical surfaceof the adapter 3 will guide the inner tube 5 down into the adapteropening 11. Simultaneously therewith, the whole of the robot head 1 ismoved forwards against the adapter 3, so that the conical part 6 of theouter tube 4 will come into abutment with the conical part 7 of theadapter 3 (see FIG. 5) so as to deform the outer tube 4 elastically.When docking has been completed, the inner tube 5 is further extendedoutwardly and down into the vehicle fuel-tank pipe 2 (see FIG. 6).

According to a preferred embodiment, the outer tube 4 is made of arelatively rigid plastic or rubber material, and the front part of theouter tube 4 includes a bellows-like section 13 which facilitates saiddeformation.

According to another preferred embodiment, the bellows-like section 13is carried by a spring-loaded tab or plate 14 whose spring-loadedattachment point 15 is fixed in relation to the robot head 1 (see FIG.2). The tab 14 is attached by means of a coil spring 16 of such strengthas to support the outer tube 4 in a generally horizontal andpredetermined position in the idle state of said tube. When the outertube 4 is deformed in the aforesaid manner, the tab 14 will rotatearound its attachment point 15 (compare FIGS. 4 and 5).

This latter embodiment obviates the need for the outer tube 4 to beself-supporting, thereby enabling the tube 4 to be made of a softermaterial, because the tube is supported by the tab 14.

The tab 14 is also rotatable about its attachment point 15 in adirection perpendicular to the plane of the paper.

According to one preferred embodiment, a position sensor 17, 18 ismounted at the tab attachment point 15, this sensor functioning to sensedeviation of the tab 14 from its rest position, in which position noload acts on the outer tube ,4 i.e. the position shown in FIG. 2. Thereference numeral 18 identifies a permanent magnet and the referencenumeral 17 identifies a magnet sensor which is connected to a dataprocessor belonging to the robot and controlling robot movement.

Because the tab 14 is bent down when the outer tube 4 is bent down andis rotated relative to the tab attachment point 15 when the outer tube 4is moved in the horizontal plane, i.e., in a direction perpendicular tothe plane of the paper, the position sensor 17, 18 is able to registerpermitted and unpermitted outward flexures of the outer tube 4. When themagnet 18 is distanced from the magnet sensor 17 to an extent which isslightly greater than that shown in FIG. 6, the magnet sensor 17 willsend to the processor a signal which indicates that bending of the outertube 4 is excessive.

Excessive bending of the outer tube 4 indicates that the robot head hasbeen positioned incorrectly in relation to the adapter 3 fitted to thefuel-tank pipe 2.

According to another preferred embodiment of the invention (see FIGS. 1and 3), there is provided on the forward end of the outer tube 4 afurther sensor 19 which is intended to coact with a sensor 20 in theadapter 3. When docking is completed, the sensor 19 and the sensor 20will be positioned opposite to one another, as shown in FIG. 3. Thissensor 19 is also connected to the aforesaid processor and is intendedto deliver a signal to the processor when docking is completed andduring the duration of said docking.

The robot processor is constructed to permit fuel to be transported inthe inner tube 5 only when the last-mentioned sensors 19, 20 and thefirst-mentioned sensors 17, 18 indicate that docking has beenimplemented and that outward bending of the outer tube 4 lies within therange permitted. This means that docking must be sufficiently accuratefor fuel to be delivered and that refuelling is immediately interruptedshould, for instance, the vehicle be driven away while refuelling is inprogress. The sensors thus enable refuelling to be effected more safely.

Although the invention has been described with reference to differentembodiments thereof, it will be understood that these embodiments can bemodified in a number of ways, for instance with regard to the dimensionsand construction of the robot head and adapter.

The present invention shall not therefore be considered limited to theaforedescribed and illustrated exemplifying embodiments thereof, sincemodifications and changes can be made within the scope of the followingclaims.

What is claimed is:
 1. Apparatus for the automatic refuelling ofvehicles comprising: a robot which includes a robot head that is movablein relation to the robot so as to bring the robot head to apredetermined position in relation to a vehicle fuel tank pipe, apositioning system for positioning the robot head during a positioningoperation, the positioning system including a first part located on therobot head and a second part placed in a predetermined position on thevehicle, wherein the robot head includes an outer tube and an inner tubewhich can be moved within said outer tube and out of said outer tube,which outer tube is resilient and wherein a free, front end of the outertube has a part in the shape of a truncated cone, said outer tube partbeing intended to be docked in a docking operation with acorrespondingly truncated conical part of an adapter during saidpositioning operation, said adapter being adapted to be attached to anupper orifice of the fuel-tank pipe, and wherein subsequent to saiddocking operation, a free forward end of the inner tube is adapted toproject out from the outer tube to a position down in the fuel-tankpipe, whereafter fuel is delivered to the fuel tank through the innertube, wherein the forward end of the inner tube has an essentiallyconical shape and wherein in said positioning operation the inner tubehas an axially displaced position relative to the outer tube such thatthe forward end of said inner tube will coact with an outer surface ofthe truncated cone of the outer tube to form a generally conical frontpart; and wherein the outer tube is resilient to such an extent thatsaid docking operation can take place when the tip of the inner tube ispositioned radially inwards of a base of the conical part of theadapter.
 2. Apparatus according to claim 1, wherein the forward end ofthe inner tube includes surface openings through which fuel is able topass out from the inner tube.
 3. Apparatus according to claim 1, whereinthe outer tube is made of a relatively rigid plastic or rubber materialand has a bellows-like section adjacent its front end.
 4. Apparatusaccording to claim 3, wherein the bellows-like section is supported by aspring-loaded tab including a spring-loaded attachment point that isfixed relative to the robot head.
 5. Apparatus according to claim 4,including a sensor mounted at said attachment point, said sensorfunctioning to detect deviation of the tab from its rest position, inwhich no load acts on the outer tube.
 6. Apparatus according to claim 1,wherein the front end of the outer tube carries a first sensor elementwhich is adapted to coact with a second sensor element carried in theadapter, said first sensor element and said second sensor element beingpositioned so that they are opposite one another when docking iscompleted.